Method of operating gas-producers.



H. L. DOHBRTY.

METHOD OF OPERATING GAS PRODUCERS.

APPLICATION FILED JAN. 17, 1911f Patented Aug. 12, 1913 $5 @GED Ma l.

itweooyzo Had ry L. Do her'fy Svwwto-z or new YORK, N. Y.

METHOD OF OPERATING GAS-PRODUCERS.

' a scess.

Specification of Letters Patent.

Patented. Aug. 12,1913.

Application filed January 17, 1911. Serial No. 503,082.

T 0 all whom it may concern:

Be it known that I, HENRY L. DOHERTY, a citizen of the United States,anda resident of New York city, in the county of New York and State ofNew York, have invented certain new and useful Improvements in Methodsof Operating Gas-Producers, of which the following is a specification;

This invention relates to a method of operating gas producers and, inparticular, to a method of operation in whlch a suit- "able flux ischarged into the producer with the fuel and theproducer operated at ahigh temperature. a

The object of my invention is to avoid the formation of clinkers in theoperation of gas producers by insuring that the ash shall be fluxed asrapidly as it is formed so that there is no danger of the sintering ofthe ash, due to incipient fusion, into large masses of clinker that willobstruct the draft through the fuel bed.

My invention consists in mixing with the oxid, silica or other flux, orsuch a mixture of two, or more of these substances as Wlll form aneasily fusible silicate with the ash of the fuel and subjecting themixture to combustion in the gas producer. The ash is thus fluxed asfast as it is liberated by the combustion of the carbon of the fuel,runs down through the interstices of the charge,

I and collects in the bottom of the gas producer from whence it istapped OK, at intervals.

In specifying aneasily fusible silicate I mean a silicate whichliquefit's sufiiciently to flow readily at the maximum temperatures.

I e. g.,tem-. between 2400 and 2600 F. I am ordinarily used in gasproducers, peratures aware that in metallurgical operations it IScustomary to fluxl off the silicious matter of the ore and fuel by theaddition of a fluxing material such as limestone; .but such operationsinvariably require a high temperature for maintaining the reactionsinvolved and silicates fusible at such tem-- peratures are readilyproduced.

My invention involves the production of compounds that are liquid atthecomparatively low temperatures used in gas producers such as arementioned 1 above. To produce compounds fusible at these tem- 5pcratures. withthe ash of fuels requires the formation of compoundshaving composifucl the proper quantity of lime, alkali, iron tions verydifferent from those of metallurgical furnace slags.

In the drawings, Figure 1 is a diagrammatic view of an arrangement ofapparatus suitable for applying my invention, and Fig. 2 is a verticallongitudinal section of the gas producer shown in Fig. 1.

. 1, is a coal-pocket into which the coal is transferred from the, carsin which it is transported. I

2 and 3 are similar pockets in which the flux to be used in making upthe charge is stored.

'4; is a mixing apparatus in which the flux and coal are thoroughlymixed.

5 is an elevator which raises the prepared fuel to the feed bin, 6,supported above the feed hopper/7, of the gas producer, 8, by thecolumns, 9.

The gas producer, 8, is simply a low shaft with thick walls ofrefractory material and an inclined bottom. A cinder notch, 10, closedby a plug, 11, of fire clay, permits of the tapping off of the fluidsilicate formed from the ash proper and the flux intentionally addeditothe charge. A twyer, 12, connected .to the pipe13 from blower 14 permitsof the air blast supplied to the gas producer bein introduced well aboveany moltenash which may have collected in the hearth 15 of producer 8. Ahood, 16, having a number of discharge port-s, 17, pretwyer 12 and,owing to its projecting edge, 18, keeps an open space in the fuel bedimmediately in front of the ports 17. Since I am able by my invention tooperate the gas producer at a relatively high temperature as mcomparedwith ordinary producer practice say around2400 F.) without causing theormation of any-serious amount of clinkers, I am not under the necessityof using steam or fiue gas to reduce the temperature in the producer, intheimanner customary in producer operation. Therefore I supply astraight air draft-current to the producer. The material which I use asflux and the quantity thereof which I add to the fuel depends entirelyupon the composition and quantity of the ash of the fuel. In some 10-calities where crude sulfate of soda is available this material mayadvantageously be used as the flux when the ash of the fuel is undulyacid. Usually, however, the most economical and available material iseither iron ore or limestone.

In nearly all parts vents the entrance of fuel or slag into the of thecountry deposits of impure hematite or limonite occur 1n greater or lessquantity, Since both the ferric and ferrous silicates, containing arelatively high proportion of base, are usually quite fusible g.almandite and fayalite) such ores as hematite and liinonite furnish aneasily procurable and satisfactory basic flux. Since this is, usually,what is required, in the majority of cases it will not be necessary toadd any other material to the fuel to supply the ingredients for. theformation of an easily fusible silicate.

In the majority foftcases, the infusibility of-ash is caused by thepresence of an ex;' cessive proportlon of alumina or s1l1ca,'or

both. While in some combinations with iron and the alkali metalsaluminium forms easily fusible silicates,- all of the simple Slllcatesof aluminium are either infusible or fusible with difliculty. Generally,there.

fore, the fusibility of a 'silcate diminishes wlth increase in theproportion of alumina;

Therefore, where the proportion of-alumina is unduly high, I add theproper proportion of iron 0I1I'0I1 3,I1d silica to form some easilyfusible double silicate of iron and alumina which may have acomposition, for instance, approximating that of the mineral almandite,-Fe Al,Si ,O which fuses at the fact that it must be rather finelycrushed to insure its decomposition to CaO and CO during the period inwhich it is passing through the gas producer. It is practicallynecessary, under the conditlons which must be met, that the limestoneshould reach the ash zone of the gas producer thoroughly cal-- oined. Itis also important that the caloined stone or lime should reach the ashzone i there is usually no difliculty in obtaining it in a fairly finecondition to facilitate its reacting with the ash particles. 'If burnedlimestonis used to mix with the fuel it can. of course, be readilyreduced to the pow dered condition by hydrating it, using care torestrict the water to just about the quantity theoreticallyrequired-allowing for the portion of the water which is evaporated bythe heat ofthe reaction and. lost as steam.

. When lime, or limestone is used as the flux fairly ure. mlnera matterin the fuel, which is a nec- The increase in the bulk of the crating agas producer on the prepared fuel which is the subject of thisapplication, since the ash may be-tapped out as frequently as necessary,without occasionlng any interruption'of the operation of the producer.

It is obvious that the exact proportion of flux added to the fuel willdepend upon the composition of the ash of the fuel and upon the kind andpurity of the flux itself. The ash of aBuck Mountain anthracite, willhave approximately the following composition, v1z.: I

SiO 45. 60% I Al O 42.75% Fe O 9. 43% CaO; 1.41 Mgo. 433% Otheringredients :48%

essary consequence. of my invention, is, in no sense, ob ectlonable bymy method of op- The proportion of ash in the coal would be about 9%. Inaton of, coal there would,

therefore, be the following weights of ashforming. ingredients, viz:

SiO :821 lb. Al O =76.9 l e. ,O,:17.0 CaO: 2.5 MgO: .6

--Estimating the Mg() in its equivalent of lime we can tak forming as'ilicat should be, at least, equal in weight to the alumina, iflime'i's to be the flux used. There fore the quantity of. lime addedshould .be about 7 6.9 minus 33:73.6 lb. In thiscase, owing 'to theabnormally high alumina, there is a' deficiency in the proportion of SiOalso. Therefore, with the lime'.'I add the proper quantity of silica. assand, to bring the proportion of'silica inv the ash mixture up to aweight about equal to the sum of the weights of alumina and lime. Sincethere are 82.1

the lime as 3.3 lb. For of easy fusibility the lime lb. of silica,already present in the ash, the

quantity of sand required would be about It is, of course. to beunderstood that I do not limit myself to operating the producer with theproportions of fluxgiven above. It is simply necessary that thequantities and kinds of flux be so adjusted that a compound of ashzandflux be formed which will be .fu-

sible at the temperature of the fuel bed'of the producer. The'mineralmatter in the ash is thus reduced to a liquid condition asfast as it isformed,-with the result that it flowsto the hearth of the. gas producer,from which it is tapped out at intervals.

Having described my invention, what I I claim is 1. The method ofoperating gas producers,

which'com'prises charging into a gas proimages v a ducer a mixture offuel and flux such-"that the mineral matter of. the charge will form aneasily fusible compound, the said flux comprising a proportioniof basicmaterial other than alumina which will establish in the charge aproportion of such bases which shall be at least equal to the aluminafree or combined present in the mixture of fuel and flux, burning saidfuel in said producer by introducing into the ignited fuel an oxidizing'draftcurrent to form combustible gas and liquid ash, and withdrawingfrom said producer the said gas and liquid ash.

2. The method of operating gas producers which comprises charging into agas producer a mixture of fuel and flux such that the mineral matter ofthe charge will form an easily fusible compound, the said fluxcomprising a proportion of basic material form with the basic other thanalumina vwhich shall establish in the chargea proportion ofsuch bases atleast equal to the alumina free or combined that. 1s present in thecharge, burning said fuel by introducing into the ignited fuel a draftcurrent of air, to form combustible gas and liquid ash, and withdrawingthe said gas and liquid ash from said producer.

3. The method of operating gas producers which comprises charging intoagas pro-- ducer a mixture of fuel and flux such that the mineral matterof the charge will forman easily fusible compound, the said fluxcomprising a proportion of basic material other than alumina which shallestablish a proportion of such bases in the charge at least equal to thealumina free or combined that is present in the charge and if neces sarya quantity of silica such that the total silica present in the chargewill be suflicient to form with the basic material of the charge asilicate fusing below 2600 F, burning combustible matter of the chargeby introducing into the ignited fuel an oxidizing draft current to formcombustible gas and liquid ash, and withdrawipg from the pro--' ducerthe gas and ashformed.

4. The method of operating gas producers which comprises charging into agas producer a mixture of fuel and flux such that the mineral matter ofthe charge will form an easily fusible compound, the said fluxcomprising a proportion of basic material other than alumina which shallestablish a proportion of such bases in the, charge at least equal tothe alumina free or combined that is present 1n the charge and ifnecessary a quantity of silica such that the total silica.

charge will be sufiicient to material of the charge a silica fusingbelow 260Q F., burning com-r bustible matter of the charge byintroducing into the ignited fuel a draft current of air to formcombustible gas and liquid ash, and withdrawing from theproducer the gasand ash formed.

present in the which comprises ,form combustible gas and ash,

5. The method of operating gas producers which comprises charginginto agas producer a mixture of fuel and flux such. that the mineral matter ofthe charge willform an easily fusible compound, the said flux comprisinga proportion of basic material other than alumina which shall'establis'ha proportion of such bases in the charge at least equal to the aluminafree or combined that is present in the charge, and if necessary aquantity of silica such as will establish a proportion of silica in thecharge approximating the proportion of total in the charge, burningcombustible matter of the charge by introducing into the ignited fuel anoxidizing draft current to form combustible gas and liquid ash, andwithdrawing from the producer the gas and ash formed.

, 6. The method of operating gas producers charging into a gas producera mixture of fuel and flux such that the mineral matter of the chargewill form an easily,fusible compound, the said flux comprising aproportion of iron oxid such as will establish a proportion of iron oxidwhose basicity together with that of the alkali or alkaline earth basespresent in the charge shall be at least equal to the aluminafree andcombined present in the charge,

burning combustible matter of the charge bydntroducing into the ignited.fuel an oxidizing draft cur ent to form combustible gas and liquid ashthe producer the gas and ash formed. V

7. The method of operating gas producers which comprises charging into agas producer a mixture of fuel and flux,the relative proportions of saidfuel andfiux being such as will establish in the charge a proportion ofiron oxid whose basicity together with that of the alkali or alkalineearth bases present in the charge shall be at least equal tothe aluminafree and combined present in the charge and a proportion of silica atleast-equal to that of the basic materials of the charge, burningcombustible matter of the charge by introducing into the ignited chargean oxidizing draft current to form combustible gas and liquid ash, andwithdrawing from said producer the gas and ash formed.

-8. The method of operating gas producers which comprises charging, intoa gas producer a mixture of fuel and flux, the relative proportions ofsaid fuel and flux being such as will establish in the charge aproportion of bases other than alumina at least equaLto the alumina freeor combined pres ent in the charge, burning combustible matter of thecharge by introducing into the ignited fuel'an oxidizing draft currentto drawing from said gas producer the gas and ash formed.

and withdrawing from and with-i 9. 'The method of operating gasproducers which comprises charging into a gas producer a mixture of fueland flux the relative proportions of'said fuel and flux and thecharacter of the said flux being such as will establish in the charge aproportion of bases the charge, burning combustible matter of the chargeby introducing into the ignited fuelan oxidizing current to formcombustible gas and ash, and Withdrawing from the producer the gas and.ash formed.

Signed at New York city in the county of New York and State of New Yorkthis 16th day of January 'A D. 1911. s

L HENRY L. DOHE-RTY.

Witnesses:

J. M. MCMILLIN, v F. L. BLACKBURN. v

